1. Field of the Invention
The present invention relates to a door lock device; and more particularly, to a drive mechanism for a combination manual and power operated door lock device having an electric actuator.
2. Description of the Prior Art
The conventional door lock device of such type includes a locking arm for performing a locking operation and an unlocking operation, a handling lever for driving the locking arm, and an actuator having a motor with a shaft, a worm gear mounted on the shaft, a wheel with a gear engaged with the worm gear and a convexed portion to be engaged with the handling lever.
For smooth transmission of the rotational torque from the motor to the handling lever, a correct mesh engagement between the worm gear and the gear of the wheel has to be assured. However, it is very difficult to obtain this engagement with reliability due to various conditions, such as thermal deformations of the related members, and so on, for example.